John was kind of a weird guy, but the guy wearing the sandals was beyond imagining, the Holy Spirit even more so. The closer I get to God through his word and the more often I experience the Holy Spirit the more I understand John's humility.

Mark 1:6-8

Now John was clothed with camel's hair and wore a leather belt around his waist and ate locusts and wild honey.
And he preached, saying, “After me comes he who is mightier than I, the strap of whose sandals I am not worthy to stoop down and untie.
I have baptized you with water, but he will baptize you with the Holy Spirit.”

Bible Gateway link